CN106906456B - A kind of preparation method of the controllable coating of the degree of cross linking - Google Patents

Abstract

The invention discloses a method for preparing a coating with a controllable crosslinking degree, which belongs to the technical field of plasma chemical vapor deposition. The method mainly includes the following steps: first, the substrate is placed in the reaction chamber of the plasma chamber, the reaction chamber is continuously evacuated, and the vacuum degree in the reaction chamber is evacuated to 10-200 millitorr, and an inert gas or Nitrogen gas provides a stable plasma environment; secondly, the monomer steam is introduced, the plasma discharge is turned on, and chemical vapor deposition is carried out; after the discharge is completed, the plasma power supply is turned off, the monomer steam is stopped, and the vacuum is continued to maintain the reaction chamber The vacuum degree is 10-200 mTorr for 1-5 minutes, then the atmosphere is vented to an atmospheric pressure, and then the substrate can be taken out. The present invention makes the coating form a dense network structure by introducing multifunctional monomers, which can not only endow the material with good physical and chemical durability, but also endow the material with excellent waterproof and oil-proof functions. The bonding of points improves the cohesive force and mechanical strength.

Description

A kind of preparation method of coating with controllable degree of crosslinking

technical field

The invention belongs to the technical field of plasma chemical vapor deposition, and in particular relates to a preparation method of a coating with a controllable crosslinking degree.

Background technique

Plasma chemical vapor deposition is a technology that uses plasma to activate reactive gases to promote chemical reactions on the surface of the substrate or in the space near the surface to form a solid film. Compared with other coating preparation methods, plasma coating technology has the following advantages: (1) dry process, the film produced is uniform without pinholes; (2) coating preparation temperature is low, and can be carried out at room temperature, effectively avoiding temperature damage to sensitive devices; (3) plasma technology can prepare not only micron-scale coatings but also ultra-thin nano-scale coatings; (4) solvent resistance, chemical corrosion resistance, and The chemical and physical properties such as heat resistance and wear resistance are stable; (5) The adhesion between the plasma polymerized film and the substrate is good.

Fluorocarbon resin has a strong C-F bond as the skeleton. Compared with other resins, it has better heat resistance, chemical resistance, cold resistance, low temperature flexibility, weather resistance and electrical properties. In addition, it has non-adhesive properties. , Non-humidity. Therefore, the fluorocarbon resin coating is especially suitable for the protection of the material surface, which can not only endow the material with good physical and chemical durability, but also endow the material with excellent waterproof and oil-proof functions. In recent years, there have been many researches and applications of fluorocarbon protective coatings prepared by plasma technology in microelectronics, optics, medical, precision equipment, and high-end clothing.

Most of the current disclosures are to obtain protective coatings by plasma-induced polymerization of monofunctional unsaturated fluorocarbon resins. However, due to the complex plasma environment and mechanism, it is difficult to control the crosslinking degree of the polymer coating through the parameters of the plasma polymerization process. For example, Masao Fujita in Japan studied the preparation of solvent-resistant and water-resistant polymer films by plasma polymerization. However, it was found that although the coating with high crosslink density has better adhesion and solvent resistance, the coating will swell and peel off due to the action of solvent. This may be due to the fact that most of the fluorocarbon resins used in plasma polymerization are monofunctional fluorocarbon monomers, and the formed coating has more linear components and insufficient crosslinking points, which seriously restricts the coating's ability to protect the substrate.

Contents of the invention

In order to solve the above technical problems, the present invention provides a method for preparing a coating with a controllable degree of crosslinking, by introducing multifunctional unsaturated monomer components in the plasma polymerization process to form a dense network structure, thereby Adjust the cross-linking degree of the polymer coating, thereby significantly improving the solvent solubility resistance, solvent penetration resistance and adhesion of the coating.

The technical scheme that the present invention adopts for realizing the above object is as follows:

A method for preparing a coating with a controllable degree of crosslinking, characterized in that it mainly includes the following steps:

(1) Place the substrate in the reaction chamber of the plasma chamber, continuously evacuate the reaction chamber, pump the vacuum in the reaction chamber to 10-200 mTorr, and inject inert gas or nitrogen to provide a stable plasma body environment;

(2) Feed monomer vapor, turn on plasma discharge, and carry out chemical vapor deposition;

Described monomer steam is:

A mixture of at least one monofunctional unsaturated fluorocarbon resin and at least one polyfunctional unsaturated hydrocarbon derivative, where the polyfunctional unsaturated hydrocarbon derivative accounts for 10%-80% by mass;

or a mixture of at least one polyfunctional unsaturated hydrocarbon derivative and at least one polyfunctional unsaturated hydrocarbon derivative;

(3) After the discharge is over, turn off the plasma power supply, stop feeding monomer steam, continue vacuuming, keep the vacuum degree of the reaction chamber at 10-200 mTorr for 1-5 minutes, and then enter the atmosphere to an atmospheric pressure, then take out the substrate. Can.

In the step (1), the substrate is a solid material, and the solid material includes electronic components, electrical components, fabrics or clothing, liquid containers, experimental equipment, film materials, and optical devices.

The volume of the plasma chamber in the step (1) is 50 to 1000 liters, and the temperature of the plasma chamber is controlled at 30 to 60°C; the flow rate of the inert gas or nitrogen gas is 5 to 300 sccm, and the inert gas is argon Or one of helium, or a mixture of helium and argon.

In the step (2): the introduction of the monomer steam is to atomize and volatilize the monomer through the feeding pump, and introduce it into the reaction chamber at a low pressure of 10 to 200 mTorr, and the flow rate of the introduction of the monomer steam is 10- 1000μL/min.

The monofunctional unsaturated fluorocarbon resin includes:

3-(perfluoro-5-methylhexyl)-2-hydroxypropyl methacrylate, 2-(perfluorodecyl)ethyl methacrylate, 2-(perfluorohexyl)ethyl methacrylate ester, 2-(perfluorododecyl)ethyl acrylate, 2-perfluorooctyl ethyl acrylate, 1H,1H,2H,2H-perfluorooctyl acrylate, 2-(perfluorobutyl) Ethylacrylate, (2H-perfluoropropyl)-2-acrylate, (perfluorocyclohexyl)methacrylate, 3,3,3-trifluoro-1-propyne, 1-ethynyl-3 , 5-difluorobenzene or 4-ethynyltrifluorotoluene;

The polyfunctional unsaturated hydrocarbon derivatives include:

Ethoxylated trimethylolpropane triacrylate, tripropylene glycol diacrylate, divinylbenzene, polyethylene glycol diacrylate, triethylene glycol divinyl ether, 1,6-hexanediol diacrylate Acrylates, ethylene glycol diacrylate, diethylene glycol divinyl ether, or neopentyl glycol diacrylate.

In the step (2), before the monomer steam is introduced, the power of the plasma discharge is set to 2-500W, and the continuous discharge time is 300-600s, and the glow discharge is carried out to bombard the substrate to pretreat the substrate surface to clean the impurities on the surface of the substrate. Activate the substrate surface.

The power of the plasma discharge in the step (2) is 2-500W, and the continuous discharge time is 600-7200s. The plasma discharge method is radio frequency discharge, microwave discharge, intermediate frequency discharge or electric spark discharge.

In the plasma radio frequency discharge process, the energy output mode of plasma radio frequency is controlled to be pulse or continuous output. When the energy output mode of plasma radio frequency is pulse output, the pulse width is 2 μs-1 ms, and the repetition frequency is 20 Hz-10 kHz. Formula voltage to increase the uniformity of film formation and reduce residual free radicals in the coating.

Compared with the prior art, the above-mentioned technical solution of the present invention has the following advantages:

(1) Plasma facilitates mutual cross-linking to form a network structure

When the plasma is glow-discharged, the active groups with higher energy in the monomer components are interrupted to form active points, and the additional active points introduced are cross-linked with each other in the plasma environment to form a network structure. It has better compactness and can effectively improve the protective performance of the film.

(2) Multifunctional monomers are conducive to the formation of crosslinked structures

Generally, monofunctional monomers are selected for plasma polymerization to obtain a loose coating structure. Moreover, the cross-linked structure is due to the fact that many active points formed by the random interruption of the monomers during the plasma glow discharge form a cross-linked structure through the way of interconnection. The present invention introduces additional crosslinking points to form a crosslinking structure by introducing other monomer components with a multifunctional crosslinking structure, so that the coating forms a dense network structure, and the introduced multifunctional The functional monomer accounts for 10-80% by weight of the monomer. Not only can it endow the material with good physical and chemical durability, but it can also endow the material with excellent waterproof and oil-proof functions.

(3) The combination of the base material and the active point of the monomer improves the binding force and mechanical strength

Under the plasma environment, the surface of the substrate is activated to obtain many active sites, which are combined with the active sites of the monomers with strong chemical bonds, so the film obtained by coating has better binding force and mechanical strength.

Detailed ways

The present invention will be described in detail below in conjunction with specific examples, but the present invention is not limited to the specific examples.

Example 1

A method for preparing a coating with a controllable degree of crosslinking, characterized in that it mainly includes the following steps:

(1) Place the base material in the reaction chamber of the plasma chamber, the base material is a solid material, the solid material is an electronic component, and the reaction chamber is continuously evacuated, and the vacuum degree in the reaction chamber is evacuated to 10 Millitorr, feed nitrogen, provide a stable plasma environment, feed nitrogen flow rate of 5 sccm;

The volume of the plasma chamber is 50 liters, and the temperature of the plasma chamber is controlled at 30°C.

(2) Introduce monomer vapor, turn on plasma discharge, and carry out chemical vapor deposition;

Described monomer steam is:

A mixture of a monofunctional unsaturated fluorocarbon resin and a polyfunctional unsaturated hydrocarbon derivative, the monofunctional unsaturated fluorocarbon resin is 1H, 1H, 2H, 2H-perfluorooctyl acrylate , the multifunctional unsaturated hydrocarbon derivative is triethylene glycol divinyl ether, and the mass percentage of the multifunctional unsaturated hydrocarbon derivative in the monomer is 10%;

The introduction of monomer steam is to atomize and volatilize the monomer through the feeding pump, and introduce it into the reaction chamber at a low pressure of 10 mTorr, and the flow rate of the monomer steam is 10 μL/min;

Before the monomer steam is introduced, the power of the plasma discharge is set to 2W, and the continuous discharge time is 600s, and the glow discharge is carried out to pretreat the substrate by bombardment, to clean the impurities on the surface of the substrate, and to activate the surface of the substrate.

The power of the plasma discharge is 2W, and the continuous discharge time is 7200s. The plasma discharge method is radio frequency discharge. The frequency is 20Hz, and a pulsed voltage is applied to increase the uniformity of film formation and reduce the residual free radicals in the coating.

(3) After the discharge is completed, turn off the plasma power supply, stop feeding the monomer vapor, continue vacuuming, keep the vacuum degree of the reaction chamber at 10 mTorr for 1 min, and then ventilate the atmosphere to an atmospheric pressure, and then take out the substrate.

Example 2

The basic process steps of this embodiment are the same as those of Example 1, and the different process parameters are as follows:

1. In step (1), the vacuum in the reaction chamber is evacuated to 50 millitorr, and an inert gas is introduced; the base material is a solid material, and the solid material is an electrical component. The volume of the plasma chamber is 200L, and the temperature of the plasma chamber is controlled at 40° C.; the flow rate of the inert gas is 50 sccm, and the inert gas is helium.

2, the monomer vapor that feeds in the step (2) is:

A mixture of a monofunctional unsaturated fluorocarbon resin and a multifunctional unsaturated hydrocarbon derivative, the monofunctional unsaturated fluorocarbon resin is 2-perfluorooctyl ethyl acrylate, and the multifunctional The unsaturated hydrocarbon derivative is diethylene glycol divinyl ether, and the mass percentage of the polyfunctional unsaturated hydrocarbon derivative in the monomer is 30%;

The introduction of monomer steam is to atomize and volatilize the monomer through the feeding pump, and introduce it into the reaction chamber at a low pressure of 50 mTorr, and the flow rate of the introduction of monomer steam is 100 μL/min;

The power of the plasma discharge is set to 150W before the monomer steam is introduced in step (2), and the continuous discharge time is 500s, and the glow discharge is carried out to bombard the substrate for pretreatment;

In step (2), the power of the plasma discharge is 100W, and the continuous discharge time is 6000s, and the plasma discharge method is microwave discharge.

3. In step (3), keep the vacuum degree of the reaction chamber at 60 mTorr for 2 minutes, and then ventilate the atmosphere to an atmospheric pressure.

Example 3

The basic process steps of this embodiment are the same as those of Example 1, and the different process parameters are as follows:

1. In step (1), the vacuum in the reaction chamber is evacuated to 200 millitorr, and an inert gas is introduced; the base material is a solid material, and the solid material is clothing. The volume of the plasma chamber is 1000L, and the temperature of the plasma chamber is controlled at 60° C.; the flow rate of the inert gas is 300 sccm, and the inert gas is argon.

2, the monomer vapor that feeds in the step (2) is:

A mixture of a monofunctional unsaturated fluorocarbon resin and two polyfunctional unsaturated hydrocarbon derivatives, the monofunctional unsaturated fluorocarbon resin is 2-(perfluorobutyl) ethyl acrylate, the The two kinds of multifunctional unsaturated hydrocarbon derivatives are diethylene glycol divinyl ether and ethylene glycol diacrylate, and the mass percentage of multifunctional unsaturated hydrocarbon derivatives in the monomer is 80%. ;

The introduction of the monomer steam is to atomize and volatilize the monomer through the feeding pump, and introduce it into the reaction chamber at a low pressure of 200 mTorr, and the flow rate of the monomer steam is 1000 μL/min;

The power of the plasma discharge is set to 300W before the monomer steam is introduced in the step (2), and the continuous discharge time is 450s, and the glow discharge is carried out to bombard the substrate for pretreatment;

In step (2), the power of the plasma discharge is 500W, and the continuous discharge time is 600s, and the plasma discharge method is electric spark discharge.

3. In step (3), keep the vacuum degree of the reaction chamber at 200 mTorr for 5 minutes, and then ventilate the atmosphere to an atmospheric pressure.

Example 4

The basic process steps of this embodiment are the same as those of Example 1, and the different process parameters are as follows:

1. In step (1), the vacuum degree in the reaction chamber is evacuated to 80 millitorr, and an inert gas is introduced; the base material is a solid material, and the solid material is a fabric. The volume of the plasma chamber is 600L, and the temperature of the plasma chamber is controlled at 45° C.; the flow rate of the inert gas is 150 sccm, and the inert gas is a mixture of helium and argon.

2, the monomer vapor that feeds in the step (2) is:

A mixture of a polyfunctional unsaturated hydrocarbon derivative and a polyfunctional unsaturated hydrocarbon derivative, the polyfunctional unsaturated hydrocarbon derivative is ethylene glycol diacrylate, the polyfunctional The unsaturated hydrocarbon derivative is diethylene glycol divinyl ether;

The introduction of monomer steam is to atomize and volatilize the monomer through the feeding pump, and introduce it into the reaction chamber at a low pressure of 80 mTorr, and the flow rate of the monomer steam is 600 μL/min;

The power of the plasma discharge is set to 400W before the monomer steam is introduced in step (2), and the continuous discharge time is 200s, and the glow discharge is carried out to bombard the substrate for pretreatment;

In step (2), the power of the plasma discharge is 300W, and the continuous discharge time is 4500s, and the plasma discharge method is microwave discharge.

3. In step (3), keep the vacuum degree of the reaction chamber at 120 mTorr for 3 minutes, and then ventilate the atmosphere to an atmospheric pressure.

Example 5

The basic process steps of this embodiment are the same as those of Example 1, and the different process parameters are as follows:

1. In step (1), the vacuum in the reaction chamber is evacuated to 160 millitorr, and an inert gas is introduced; the base material is a solid material, and the solid material is an electronic component. The volume of the plasma chamber is 800L, and the temperature of the plasma chamber is controlled at 55° C.; the flow rate of the inert gas is 260 sccm, and the inert gas is argon.

2, the monomer vapor that feeds in the step (2) is:

A mixture of a polyfunctional unsaturated hydrocarbon derivative and a polyfunctional unsaturated hydrocarbon derivative, the polyfunctional unsaturated hydrocarbon derivative is ethylene glycol diacrylate, the polyfunctional The unsaturated hydrocarbon derivative is neopentyl glycol diacrylate;

The introduction of monomer steam is to atomize and volatilize the monomer through the feeding pump, and introduce it into the reaction chamber at a low pressure of 80 mTorr, and the flow rate of the introduction of monomer steam is 800 μL/min;

The power of the plasma discharge is set to 500W before the monomer steam is introduced in step (2), and the continuous discharge time is 300s, and the glow discharge is carried out to bombard the substrate for pretreatment;

In step (2), the power of the plasma discharge is 100W, and the continuous discharge time is 7000s, and the plasma discharge method is radio frequency discharge.

3. In step (3), keep the vacuum degree of the reaction chamber at 100 mTorr for 3 minutes, and then ventilate the atmosphere to an atmospheric pressure.

The coating prepared by the method described in the above-mentioned embodiment 1 to embodiment 5 has excellent resistance to organic solvent dissolution, and the test results are as follows:

Claims (7)

1. A method for preparing a coating with a controllable degree of crosslinking, characterized in that: mainly comprising the following steps: (1) Place the base material in the reaction chamber of the plasma chamber, continuously evacuate the reaction chamber, pump the vacuum in the reaction chamber to 10-200 millitorr, and feed inert gas or nitrogen; (2) Feed monomer vapor, turn on plasma discharge, and carry out chemical vapor deposition; Described monomer steam is: A mixture of at least one monofunctional unsaturated fluorocarbon resin and at least one polyfunctional unsaturated hydrocarbon derivative, where the polyfunctional unsaturated hydrocarbon derivative accounts for 10%-80% by mass; or a mixture of at least one polyfunctional unsaturated hydrocarbon derivative and at least one polyfunctional unsaturated hydrocarbon derivative; The monofunctional unsaturated fluorocarbon resin includes: 3-(perfluoro-5-methylhexyl)-2-hydroxypropyl methacrylate, 2-(perfluorodecyl)ethyl methacrylate, 2-(perfluorohexyl)ethyl methacrylate ester, 2-(perfluorododecyl)ethyl acrylate, 2-perfluorooctyl ethyl acrylate, 1H,1H,2H,2H-perfluorooctyl acrylate, 2-(perfluorobutyl) Ethylacrylate, (2H-perfluoropropyl)-2-acrylate, (perfluorocyclohexyl)methacrylate, 3,3,3-trifluoro-1-propyne, 1-ethynyl-3 , 5-difluorobenzene or 4-ethynyltrifluorotoluene; The polyfunctional unsaturated hydrocarbon derivatives include: Ethoxylated trimethylolpropane triacrylate, tripropylene glycol diacrylate, divinylbenzene, polyethylene glycol diacrylate, triethylene glycol divinyl ether, 1,6-hexanediol diacrylate Acrylates, ethylene glycol diacrylate, diethylene glycol divinyl ether, or neopentyl glycol diacrylate; (3) After the discharge is over, turn off the plasma power supply, stop feeding monomer steam, continue vacuuming, keep the vacuum degree of the reaction chamber at 10-200 mTorr for 1-5 minutes, and then enter the atmosphere to an atmospheric pressure, then take out the substrate. Can. 2. the preparation method of a kind of coating with controllable degree of crosslinking according to claim 1, is characterized in that: in described step (1), base material is solid material, and described solid material comprises electronic component, electric component , fabrics or clothing, liquid containers, laboratory equipment, membrane materials, optical devices. 3. The preparation method of a coating with a controllable degree of crosslinking according to claim 1, characterized in that: the volume of the plasma chamber in the step (1) is 50 to 1000 liters, and the temperature of the plasma chamber The temperature is controlled at 30-60° C.; the flow rate of feeding inert gas or nitrogen is 5-300 sccm, and the inert gas is one of argon or helium, or a mixture of helium and argon. 4. the preparation method of a kind of coating with controllable degree of crosslinking according to claim 1, it is characterized in that: in described step (2): passing through monomer steam is that monomer is atomized by feeding pump , volatilization, introduced into the reaction chamber by a low pressure of 10-200 mTorr, and the flow rate of the monomer vapor introduced is 10-1000 μL/min. 5. The preparation method of a coating with a controllable degree of crosslinking according to claim 1, characterized in that: the power of the plasma discharge is set to 2-500W before the monomer vapor is introduced in the step (2) , the continuous discharge time is 300-600s, and the substrate is subjected to bombardment pretreatment by glow discharge. 6. The preparation method of a coating with a controllable degree of crosslinking according to claim 1, characterized in that: the power of the plasma discharge in the step (2) is 2 to 500 W, and the continuous discharge time is 600 to 500 W. 7200s, the plasma discharge method is radio frequency discharge, microwave discharge, intermediate frequency discharge or electric spark discharge. 7. The preparation method of a coating with controllable crosslinking degree according to claim 6, characterized in that: the energy output mode of controlling the plasma radio frequency in the plasma radio frequency discharge process is pulse or continuous output, and the plasma radio frequency When the energy output mode of body radio frequency is pulse output, the pulse width is 2μs-1ms, and the repetition frequency is 20Hz-10kHz.